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Any current generation subaru FWF's out there

Regarding cowl pressures, the important thing is to actually measure them and not assume anything about how air is going to flow. A simple gauge that measures inches of water can be had for under $50 and save many headaches if it just gets used. From my experience, radiators, oil coolers, and inter coolers will perform pretty well once the differential pressure across them gets up around 6 or 7 inches. It only takes a little leakage to allow the differential pressure to equalize and destroy the flow. Air scoops and NACA inlets cannot do their job if they are having to exit air into a high pressure area, like the inside of the cowling. The pressure in my cowling behind the radiators will have around 7" water column pressure, so to get good flow to another exchanger requires the air inlet or scoop to overcome this pressure before any flow can take place. It is easy to waste a bunch of time putting things together that looks like it will allow good air flow and cooling...
Indeed. I helped one of the sport class reno racers and got him to instrument the plane briefly. I ran some calcs based on the measurements and made some recommendations. He picked up about 15 kts in the first iteration! Unfortunately, I think he got impatient with the process and I had a hard time getting any more readings.

I also got to compare notes with Dave Anders for a couple of hours at the race and concluded that both in the race plane and in most of the planes I've seen, there is likely quite a bit of low hanging fruit in the cooling system, but as you say, you can't assume, you have to measure, unless you are a lot better than me. :) At least theoretically, I also see some apparent low hanging fruit in water cooled engines, but I've not actually had opportunity to touch one.
 
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Anyone have an exploded assembly view of one of these gearboxes or photos? I've not followed, but as a mechanical engineer I'm quite curious.

Here is exploded view with parts for the Verner 133 (80 HP, twin). Verner used a belt in their earlier versions, but switched to this gearbox. The exact same principle is used on the newer Rotax 912iS, but different design (the ULS also has a free play for proper idle operation, but that is removed on the iS).

I'm not an expert on this either, but as an engineer working with dynamic analysis of turbines (and stuff) I'm curios how things work. The "solution" is rather straight forward and obvious once you think about it; spring and dry friction (Coulomb) damper. The dangers of TV is at low RPM and low propeller load, and during start/stop. This is due to the rotating inertia of the propeller vs torque peeks from the engine and changing direction of forces during no load conditions that also could cause high peek values. At those conditions you want to protect the gears from overload and fatigue. At all other conditions, you want the gear to act as a solid body. The spring will soften the forces, and the clutch will dissipate energy, a shock absorber. When the dynamic forces are below a pre-set value determined by the pre-set spring force and clutch, the whole assembly acts as one unit. So you can build a light weight gear that lasts "forever". To use rubber instead of spring/dry friction will also work I guess since rubber acts both as spring and damping, but the gear will never act as one solid unit, so energy is constantly dissipated causing reduced life time and maybe even a heat problem, maybe also higher order TV. That is my theory on this (right or wrong).

http://www.vernermotor.com/pdf/iomvm133m_s.pdf


Regarding cooling. ULPower has included in their manual how this setup MUST be for the engine to operate without overheating (or without excess drag depending how you look at it). Look at page 30 http://www.ulpower.com/engines/manuals/350/UL350i-UL350iF-UL350iS-UL350iHPS-installation-manual.pdf
If you stick to the manual regarding those pressure drops, the engine will run in any airframe without any heating problems.

Rotax also have stuff like this available, but their site is a bit more confusing.


When looking at the Viking engine site, none of this basic engineering stuff is available, and that should ring some bells here and there. I believe the Honda engine is perfect for the job, much more so than any Subaru, because it also runs without problems in outboard marine application. But if Egg's setup is perfect is another story altogether.
 
Here is exploded view with parts for the Verner 133 (80 HP, twin).

Interesting design.

http://www.vernermotor.com/pdf/iomvm133m_s.pdf

I suspect more than a few readers are confused by the use of the word "clutch" in this application. It is not a clutch in the conventional sense of the word, examples being:

Any of various devices for engaging and disengaging two working parts of a shaft or of a shaft and a driving mechanism.

or

a coupling used to connect and disconnect a driving and a driven part (as an engine and a transmission) of a mechanism

I suspect the word was borrowed with the parts. The diagrams do in fact illustrate clutch plates as used for power transmission and disengagement, in a style typical for motorcycles and small diameter, multiplate applications. However, in this case the clutch plates cannot disengage the drive train. The plates merely serve as a friction damper/torque limiter in parallel with a soft element (the 13K-05-45 springs). As noted, at low torque power is transmitted via the plates. When start up intertias, resonant oscillating torque, or even the normal torque oscillation of internal combustion exceeds the frictional capacity of the plates, they slip and power transmission is assisted by the springs. When slipping the plates serve as a true frictional damper, converting mechanical power to heat.

I have no idea how well the system really works. I would note that static friction is higher than dynamic friction. I'd also note that continuous plate slippage would add a lot of heat to the system, and friction plate lifespan would be an issue. Last, its performance would vary with wear.

I see one design detail I do not like at all, but i'll try to remain open-minded. The 13M-05-04 damper body is keyed to the crankshaft (13S-00-86 key).

To use rubber instead of spring/dry friction will also work I guess since rubber acts both as spring and damping, but the gear will never act as one solid unit, so energy is constantly dissipated causing reduced life time and maybe even a heat problem, maybe also higher order TV. That is my theory on this (right or wrong).

Lovejoy publishes technical information for their popular line of rubber couplers, including damping coefficient. It is very small, so heating is equally small in normal operation. That said, yes, if you spec a coupler that is too soft you can damage it with both heating and mechanical forces.

It is possible to develop a viscous damper in parallel with a soft element. Dana has a patent on one in parallel with springs. I built one for a Suzuki conversion in parallel with a Centaflex rubber element. A viscous damper eliminates all the wear issues of a damper based on surface contact. This one sheared a viscous silicone fluid between large area close fitting surfaces (0.010' clearance). The large area also offered a huge capacity for heat dissipation, thus fluid viscosity could be treated as stable.

Here I'm pumping in silicone after having it apart for for inspection. Education and recreation....

24mb5w0.jpg
 
That's a clever gearbox design. I imagine much more important on a 2 cylinder than a 4.

It is interesting that they prescribe an exit area of 500% of inlet. That will make for some cooling drag!:eek:
 
Regarding cooling. ULPower has included in their manual how this setup MUST be for the engine to operate without overheating (or without excess drag depending how you look at it). Look at page 30 http://www.ulpower.com/engines/manuals/350/UL350i-UL350iF-UL350iS-UL350iHPS-installation-manual.pdf
If you stick to the manual regarding those pressure drops, the engine will run in any airframe without any heating problems.

Rotax also have stuff like this available, but their site is a bit more confusing.
Interesting. From memory (I'm on a flight to Dallas right now) lycomings like about 5" of water. It sounds like UL can deal with less than an inch (20mm). I wonder if I'm forgetting something. That's a big difference! Cooling this thing with minimal drag should be much easier. It is also interesting that they don't prescribe a picolo tube for the plenum. Measuring the reno racer, I found that inlet velocity was substantial enough to alter readings quite abit, but that plane was doing north of 375 indicated (don't recall if he is calibrated in mph or kias, I think the latter).
 
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Interesting. From memory (I'm on a flight to Dallas right now) lycomings like about 5" of water. It sounds like UL can deal with less than an inch (20mm). I wonder if I'm forgetting something. That's a big difference!

Scott, your memory is working fine. Using the IO-360 chart, 5"H2O drop at 5000 PA (measured at the engine face) is enough to cool 140 hp at <400 CHT and 0.5 BSFC, standard day OAT.

I suspect the little UL motor has a higher fin area/HP ratio.
 
Makes me wonder if the rpm should be labeled as prop, not crank??

And, where did they take the torque reading from?? Crank or prop flange??

I agree, 5252 rpm is the standard crossover point for HP/TQ charts------at least for the 50 or so years I have been paying attention to such things.

By the way, anybody remember what this thread is supposed to be about :D
 
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However the graph on p.13 seems to violate all that is holy with engines. That is that torque and HP curves cross at 5252 RPM...

....in English units. The 5252 figure comes from 33,000/2pi, 33,000 pounds feet per minute being the rough equivalent of Watt's example draft horse....180 lbs pulled 181 feet in one minute.

Anyway, no newton-meters, just pounds and feet.

Look at the dyno chart. Torque at 5200 RPM is 109 Nm, which converts to 80 lbs-ft. Using the HP scale values on the left margin, find 80 on the graph. It's right there at the intersection of HP and 5252.
 
Some thread drift here but an interesting discussion. Dan always posts thoughtful insight.

UL outlet to inlet area at 500% is nonsense as already observed. There is no science in that design, just guaranteed high drag. Great cooling at the expense of high cruise drag does not impress me. In good liquid cooled designs we are down to 50-60% of inlet area in cruise for exit area using variable exit geometry and about 125% in climb. We can cool 200hp with as little as 28 square inches of inlet area even in hot climates with a proper rad and duct design.

I am not fan of slipping metal clutches with regard to limiting TV in gearbox designs. Make sure we are talking about clutches and not dampers. The Rotax clutch does not slip in normal flight operation.

We know it is pretty essential with aero gearboxes to have some TV absorber mechanism inline if the gearset is to last decently. Many ways to accomplish this, some ways are better than others.
 
It's Verner that specify 5/1 outlet area, not UL. UL specify min 20 mm pressure drop at 120 km/h (along with temperatures). The Verner engine is mostly used in Trikes and other slow flying installations, often uncowled. 5/1 sounds reasonable as a starting point for a typical Verner installation to achieve enough pressure drop.

It was a question about gears that works. The Verner gear works, Rotax with the clutch works. It's a design that has a proven track record for simply working. That is why Rotax use a new design with no free play, only clutch (damping) and spring in their new iS. The 912's with no clutch are much more specific regarding propeller inertia (and no CS prop for instance).

It is also interesting looking at 4 stroke outboard engines regarding cc.
75 - 100 hp : 1500cc
100 - 150 hp : 2500 cc
150 - 250 hp : 3500 cc
250+ hp : 4500+ cc

Dan, does the gear run well?
 
Sorry, I meant the Suzuki conversion with the viscous coupling/damper you mentioned earlier. I'm just curious about how it runs.
 
Sorry, I meant the Suzuki conversion with the viscous coupling/damper you mentioned earlier. I'm just curious about how it runs.

I think the airplane is with its third owner now. I don't know how many hours are on it. The basic system was a belt drive with a properly sized Lovejoy Centaflex soft element between the crank and the lower sprocket. It replaced a drive purchased from a vendor which had turned out to be a torsional and mechanical disaster (sound familiar?). Mechanical issues aside, the operational problem was a huge resonant amplitude at about 1800 RPM.

I have a good friend who had just finished writing custom software for modeling torsional vibration. He wished to proof the code, so we entered into a project; we would model the old drive, then work the model to determine the inertias and stiffnesses of a optimal drive. I would then design and build a new drive to match the optimized model, which we would then instrument to record mean and oscillating shaft torque for comparison with the code's predictions. And that's what we did.

The math model indicated a maximum (WOT) resonant amplitude over 1500 ft-lbs @ 1800 RPM for the original vendor-supplied drive. We did not instrument that drive.

The new drive matched the code simulation pretty well, and the resonant amplitudes were reasonable. This is a plot of oscillating torque taken from a strain gauge array on the propshaft, steady state throttle. Peak amplitude is now 180 ft-lbs at around 1200 RPM. Still a "prohibited RPM range", but the location is convenient and it won't break the system:

24qssaf.jpg


The viscous disk damper was an experimental add-on fired by pure curiosity. Here is the same system as above, but with the addition of the damper:

2rwosjs.jpg


The mechanical design of the damper was driven by convenience; we were interested in the data, not a product. As a quick add to the existing system it was not very robust, and was removed before the airplane left for a new home. Given the opportunity to properly incorporate a viscous damper, I think it could work pretty well.
 
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Marcotte

The Marcotte boxes don't break but the rubber bushing couplers don't last forever. Depending on the engine and prop, the lifespan seems to be between 150 and 350 hours. Mine were pretty beat at the 357 hour mark. They cost about $60 to change and a few hours, also easy to inspect. Two users have reported much less severe F1/ F2 with heavier flywheels installed so I'm going that route this time as well. Will be an interesting experiment.

Who actually is Guy Marcotte? Has anyone actually met him?

From Marcotte's website, http://www.glasairproject.com/Marcotte/index.html, it's clear he is not a marketing graduate.

Is he an actual licensed mechanical engineer?

Some guy in his garage with a used CNC machine and a 50 ton press?

A vaporous cloud with a website?

Supposedly Guy Marcotte has been selling these since 1996. That is 16 years. Is he on the verge of retirement now? What happens to the business then?

It's baffling to me that someone has a website selling these psru's, but offers next to nothing as far as information regarding their actual knowledge and educational background. Nor is there any history of the number of units sold, customer contact list, currently flying units, etc. Company profile? Mission statement?

Are they made in China? Who knows?

What type of metal for the various components? Who knows.

Selling them since 1993? How many? 2? 2,000?

In stock? Custom made to order? How long? Payment policies?

Come on man, seriously? This is how you market your product? It's 2013 now.

Guy, how about posting your experience, educational background and product information for potential customers to make an educated purchasing decision from?

In the meantime, I am going to go over to Indianapolis speedway with a wrench and greasy coveralls. I should be able to land a job working on race cars in about 30 seconds, because I have a webpage that shows me with a wrench and greasy coveralls that says "Since 1980."

What more do they need to know really?
 
Who actually is Guy Marcotte? Has anyone actually met him?

From Marcotte's website, http://www.glasairproject.com/Marcotte/index.html, it's clear he is not a marketing graduate.

Is he an actual licensed mechanical engineer?

Some guy in his garage with a used CNC machine and a 50 ton press?

A vaporous cloud with a website?

Supposedly Guy Marcotte has been selling these since 1996. That is 16 years. Is he on the verge of retirement now? What happens to the business then?

It's baffling to me that someone has a website selling these psru's, but offers next to nothing as far as information regarding their actual knowledge and educational background. Nor is there any history of the number of units sold, customer contact list, currently flying units, etc. Company profile? Mission statement?

Are they made in China? Who knows?

What type of metal for the various components? Who knows.

Selling them since 1993? How many? 2? 2,000?

In stock? Custom made to order? How long? Payment policies?

Come on man, seriously? This is how you market your product? It's 2013 now.

Guy, how about posting your experience, educational background and product information for potential customers to make an educated purchasing decision from?

In the meantime, I am going to go over to Indianapolis speedway with a wrench and greasy coveralls. I should be able to land a job working on race cars in about 30 seconds, because I have a webpage that shows me with a wrench and greasy coveralls that says "Since 1980."

What more do they need to know really?

Marketing has never been Guy's strong point and English is his second language.

He is not a mechanical engineer. As far as I know he was an industrial gearbox technician and machinist.

Yes, he is on the verge of retirement now and the future of the gearbox support and manufacturing is unclear.

Technical info has always been spotty as with all the other auto conversion suppliers and you will not find this sort of reliable unbiased info on most other vendors sites either, usually just glowing reviews, and sanitized statements.

These are not made in China. I believe the gear sets are made in the US and the rest of the parts in Canada. Shafts are 4140, gear housing 6061T6, Timken bearings.

My educated guess on number of units sold is under 300. I know a number of people flying them and I own 3 of them.

Not usually in stock, made to order, minimum wait 8 weeks, max wait up to 6 months. Used to be 50% down and the remainder just prior to delivery.

Yes, Guy could have sold many, many more of these with a proper, informational website. Deliveries have always been slow and communication and contact slow and spotty.

Other than Autoflight in NZ and a handful of others, you will find pretty much all other PSRU makers and FF vendors have limited engineering capability, virtually no real world testing and make unrealistic claims, while keeping failures a bit secret. This is why most are, or soon will be, defunct.

I don't think you will find Guy on this site or any others for that matter.

If you plan to use a Subaru and a PSRU, drop me a PM and I can help steer you somewhere. If you want an easier life, install a traditional engine.:)
 
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Marcotte

Other than Autoflight in NZ and a handful of others, you will find pretty much all other PSRU makers and FF vendors have limited engineering capability, virtually no real world testing and make unrealistic claims, while keeping failures a bit secret. This is why most are, or soon will be, defunct.

Thanks for the info.

It's hard to believe that with all the manufacturing knowledge and equipment in the US, that what we have to choose from is a guy in Canada on the verge of retirement and a guy in New Zealand who may also be on the verge of retirement.

Someone please buy the rights to make the Marcotte gearbox here in the US!

If the guess as to units sold is 300. Take a kit completion rate of about 20%, that would leave 60. You can probably lop off another 20 for guys changing their mind about engines. So there should be about 40 units actually installed in airplanes. The remaining 260 units are probably collecting dust on a bench somewhere.

Who has those flying units?

Do you have all three Marcotte units installed on flying planes?
 
Eric,

I noticed you're new here. Welcome aboard. Have you read all the PSRU information in the archives? You'll find it under "Forums" and then "Alternative Engines".
 
Thanks for the info.

It's hard to believe that with all the manufacturing knowledge and equipment in the US, that what we have to choose from is a guy in Canada on the verge of retirement and a guy in New Zealand who may also be on the verge of retirement.

Someone please buy the rights to make the Marcotte gearbox here in the US!

If the guess as to units sold is 300. Take a kit completion rate of about 20%, that would leave 60. You can probably lop off another 20 for guys changing their mind about engines. So there should be about 40 units actually installed in airplanes. The remaining 260 units are probably collecting dust on a bench somewhere.

Who has those flying units?

Do you have all three Marcotte units installed on flying planes?

The gearboxes tend to be sold because they are pricey and easy to unload if a project gathers dust for too long and move onto the next project which may or may not get done.;) Certainly, there are not 300 flying now. The bulk of the deliveries were 5-10 years ago. Many auto powered projects have a short flying lifespan or limited hours anyway.

Russell Sherwood is the other notable user of Marcotte. He had multiple failures of 2 other types of planetary boxes, switched to Marcotte a few years back and has had zero issues. He pushes his hard behind a SARL championship winning 6 cylinder EG33.

I am flying only one box at the moment, other is on my RV10 and one is a spare as the future is cloudy. The Marcotte is a solid box but has some minor problems still and could use a better TV solution. I am testing some things soon on mine.

Many people have tried to produce good PSRUs and most have failed due to the lack of engineering and testing. Real World Solutions has a successful planetary box mainly for Wankels, designed by an engineer and it has quite a lot of successful air time. RDM has had a box in development and testing for several years which may be due to be released soon, mainly developed for high power 6 cylinder Subarus. Geared Drives offers a box for Subaru but had an early gear failure for undetermined reasons, that company is under new ownership now but nothing much has happened in the last 3 months with them. There are other PSRUs from Europe, mainly for low powered engines and a another planetary box from Canada but it has had some problems with planet gear lubrication failures.

Read up on torsional vibration here on VAF. This is a vexing problem, especially with 4 cylinder engines.

Autoflight in NZ is still in business I believe but their website has been down for a while. They produce other machined goods, not just gearboxes.

Guy Marcotte may be interested at some point in selling off the design rights, I have not talked with him for a bit.

Just be aware that most auto conversions are not all roses and a good PSRU is often one of the big problems. My standard advice is: if you are not an engineer or gearhead/ machinist/ fab guy/ engine builder, don't go the auto engine route, use a traditional engine.
 
Just be aware that most auto conversions are not all roses and a good PSRU is often one of the big problems. My standard advice is: if you are not an engineer or gearhead/ machinist/ fab guy/ engine builder, don't go the auto engine route, use a traditional engine.

That is good advice indeed.

It seems like Marcotte has a basically solid product. It would be a shame to see it disappear when he retires. Why reinvent the wheel when you have a product that is very workable within reasonable limits.

Don't get me started on Real World Solutions website. A marketing disaster as far as experimental aviation product goes. Ughhh

I was actively exchanging emails with Phyllis at Geared Drives regarding the LS1 engine. But unfortunately, both her and her father Bud, were killed in that plane crash not long ago. The website is still up, but not updated because nobody else had the passwords to access it. So it just hangs out there in cyberland like a ghost. Bud was the main man with the development. And his daughter was the main administrative person. With both of them gone now, it's unlikely to progress.

Well if Marcotte is interested in selling the rights to make the gearboxes, you may be in a good position to keep the ball rolling if you are so inclined. Certainly better than coming up with a design from scratch.

It would be interesting to find out from him the customer list and who actually has them flying as of 2013.
 
Interesting comment about 'marketing disaster'. You can find less disastrous *looking* web sites for aviation products, some (a lot) of which are much more disastrous for purchasers of the products marketed there.

Here's a rough quote of something buried in the Real World Solutions web site, if you really do your research:

'We fly what we sell.'

That's pretty strong marketing, in this market, and not something that many suppliers can honestly claim. Know your supplier. And if you don't have the skill set or know someone who does, it's better to stay away from alternative engines (& maybe, experimentals in general).

In my opinion, the real reason alternative engines have such a bad rep is not the engine; it's the builder (and unqualified/unethical systems suppliers).

Just hoping I don't add to the bad rep....

Charlie
Renesis FWF in progress on a -7
 
That is good advice indeed.

It seems like Marcotte has a basically solid product. It would be a shame to see it disappear when he retires. Why reinvent the wheel when you have a product that is very workable within reasonable limits.

Don't get me started on Real World Solutions website. A marketing disaster as far as experimental aviation product goes. Ughhh

I was actively exchanging emails with Phyllis at Geared Drives regarding the LS1 engine. But unfortunately, both her and her father Bud, were killed in that plane crash not long ago. The website is still up, but not updated because nobody else had the passwords to access it. So it just hangs out there in cyberland like a ghost. Bud was the main man with the development. And his daughter was the main administrative person. With both of them gone now, it's unlikely to progress.

Well if Marcotte is interested in selling the rights to make the gearboxes, you may be in a good position to keep the ball rolling if you are so inclined. Certainly better than coming up with a design from scratch.

It would be interesting to find out from him the customer list and who actually has them flying as of 2013.

RWS is a solid company run by an honest, straight shooting and well respected engineer who flies what he sells, issues SBs and ships out new parts if something is not right at his expense. Few if any existing FF parts suppliers can make any of those claims. I'd be less concerned about "marketing" in the conventional sense and far more concerned about background and real world results if you will pardon the pun. Tracy Crook is one of the few shining stars in this business who is not only still around after more than a decade in the business but also respected by his clients.

Geared Drives was acquired by a new owner a few months back, not sure what is happening there. He will have to put some fine people in place to replace Bud and Phyllis and make it all fly again- probably a big task. In the case of these gearboxes, I'll again stress that a successful V8 gearbox design does not translate to one that works on a four necessarily. The TV issues are far worse in the latter case and the de-clutch arrangement does nothing to solve the typical TV issues occurring at F2. Bud while a very talented guy, was not a professional engineer to my knowledge and no TV testing or analysis was done on his gearbox designs.

I am not inclined to look into picking up the Marcotte design/ manufacturing rights, too many projects on the burner and I don't have the money anymore to invest in making it what it should be. Guy probably does not know who is currently flying his PRSUs. I'd join Flysoob and poll the members there. Most users had Subaru engines I believe. Some people have posted some of the problems they have seen with these boxes over the years.

The most proven PSRUs for Subarus were the Parnham and RAF belt drives. Both designs have a couple hundred thousand flight hours on them to date.
 
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There are very few good options for PSRU's out there. I think the Eggenfellner Gen3 with a dual mass flywheel is a very reliable option. There are many flying (maybe 100?) with no catastrophic failures. I have 560 hours on mine. The dual mass flywheel seems to act like a damper and preserves the gearbox. The only issues have been with non dual mass installations and they were not catastrophic failures. Too bad Jan didn't stick with the 4 cylinder package. With the right combination of parts it's a great engine, PSRU, and prop for an RV.

-Andy
 
There are very few good options for PSRU's out there. I think the Eggenfellner Gen3 with a dual mass flywheel is a very reliable option. There are many flying (maybe 100?) with no catastrophic failures. I have 560 hours on mine. The dual mass flywheel seems to act like a damper and preserves the gearbox. The only issues have been with non dual mass installations and they were not catastrophic failures. Too bad Jan didn't stick with the 4 cylinder package. With the right combination of parts it's a great engine, PSRU, and prop for an RV.-Andy

You don't have a dual mass flywheel, and it's not a damper.
 
There are very few good options for PSRU's out there. I think the Eggenfellner Gen3 with a dual mass flywheel is a very reliable option. There are many flying (maybe 100?) with no catastrophic failures. I have 560 hours on mine. The dual mass flywheel seems to act like a damper and preserves the gearbox. The only issues have been with non dual mass installations and they were not catastrophic failures. Too bad Jan didn't stick with the 4 cylinder package. With the right combination of parts it's a great engine, PSRU, and prop for an RV.

-Andy

There have been catastrophic failures of the Gen 3 boxes. Do you remember the one that ended up on federal land last year? "Very reliable" is not the words I'd use to describe these boxes. Broken welds, broken input shafts, disintegrating flywheels, bearings shedding metal, leaking seals, serious F1 kickback for a good percentage of users etc.

I am glad your box is working well with over 500 hours on it, many others have not been so fortunate.

I do agree that Jan should have stuck with the fours and that with the right combination of parts, they can work well and be more competitive in the weight department.

I am glad to see your post here so people can see that there are successes. You are happy and stuck with it unlike many others.:)
 
Marketing

Interesting comment about 'marketing disaster'. You can find less disastrous *looking* web sites for aviation products, some (a lot) of which are much more disastrous for purchasers of the products marketed there.

True enough I imagine. But if you have a product that works well and are standing behind it with good support, it baffles me that many just drop the ball on marketing it effectively. It's almost like they are saying, well, we really don't want THAT much money coming in.

But I digress.

Agreed that any alternative engine is going to eat up a lot of extra time on projects. A solid FWF setup instead of piece meal stuff would go a long way to helping expand our options.

William Wynne seems to have managed it with the Corvair setup he has developed. No dreaded PSRU to deal with on that since it is direct drive.

The biggest draw of the alternative engines is probably cost. Who really wants to shell out 25-35 grand for an engine. I don't relish writing that check.

But lots of time and cost is wasted on alternatives because few really come up with a FWF complete workable reliable setup. And many spend more time tinkering with it, rather than out flying. Or those people who claim to have workable and reliable setup, don't share the information. So you are just left with bits and pieces of sketchy information on how "they" did it. But nothing really concrete.

I understand why Vans only recommends the engines he does for the RVs.
 
True enough I imagine. But if you have a product that works well and are standing behind it with good support, it baffles me that many just drop the ball on marketing it effectively. It's almost like they are saying, well, we really don't want THAT much money coming in.

But I digress.

Agreed that any alternative engine is going to eat up a lot of extra time on projects. A solid FWF setup instead of piece meal stuff would go a long way to helping expand our options.

William Wynne seems to have managed it with the Corvair setup he has developed. No dreaded PSRU to deal with on that since it is direct drive.

The biggest draw of the alternative engines is probably cost. Who really wants to shell out 25-35 grand for an engine. I don't relish writing that check.

But lots of time and cost is wasted on alternatives because few really come up with a FWF complete workable reliable setup. And many spend more time tinkering with it, rather than out flying. Or those people who claim to have workable and reliable setup, don't share the information. So you are just left with bits and pieces of sketchy information on how "they" did it. But nothing really concrete.

I understand why Vans only recommends the engines he does for the RVs.

Heavy marketing does not work on products like these IMO. These are low demand, low production pieces by nature. Tracy is basically saying here is what I offer, here is the track record, if you need the piece, I'd be happy to sell it to you. You can't really sell a PSRU to someone who doesn't need it.

WW had his share of failures in the early days and learned a lot that he didn't know to begin with even though he always called himself the "Corvair Authority". Not using the factory forged, nitrided cranks in his engines initially was foolish, regrinding 110 cranks without proper attention to the fillets was another mistake. Some of the other recommendations are just a waste of money IMO as an ex- builder of these engines for performance and racing use.

These days, they seem reasonably reliable but not exactly cheap any more and they don't work for RVs.

Cost is the big factor usually and the successful conversions cost a fraction to acquire and overhaul. The unsuccessful ones are certainly more expensive as people end up buying the traditional engine in most cases anyway.

Things have progressed quite a bit in the last 5 years I think. We have many successful VW, Corvair, Subaru and V8 conversions flying now. It is important to follow a proven recipe however. Most of the mistakes have been made by someone else before so there is no need for a new guy to repeat them. Join the appropriate forum and get the right information before you start down this path.
 
Marketing

Heavy marketing does not work on products like these IMO. These are low demand, low production pieces by nature. Tracy is basically saying here is what I offer, here is the track record, if you need the piece, I'd be happy to sell it to you. You can't really sell a PSRU to someone who doesn't need it.

True. But we could flip that and say then, why do any marketing at all? Not everyone drinks coffee. Why have any internet presence at all? Just go with word of mouth advertising. And I am sure some do, and are perfectly fine with the few sales they get trickling in.

No matter how small your market may be, it is still "x" number of potential buyers each year. And new people getting into aviation each generation who may not be familiar at all with your product, experience, etc. So why not do your best to capture that market.

Too many websites are just a jumble of information and hyperlinks upon hyperlinks. It would really benefit many to get a much better handle on their websites, marketing and keep them properly updated.
 
True. But we could flip that and say then, why do any marketing at all? Not everyone drinks coffee. Why have any internet presence at all? Just go with word of mouth advertising. And I am sure some do, and are perfectly fine with the few sales they get trickling in.

No matter how small your market may be, it is still "x" number of potential buyers each year. And new people getting into aviation each generation who may not be familiar at all with your product, experience, etc. So why not do your best to capture that market.

Too many websites are just a jumble of information and hyperlinks upon hyperlinks. It would really benefit many to get a much better handle on their websites, marketing and keep them properly updated.

A web presence is important these days for sure if you make or sell any product or service. In the case of RWS, the website and WOM work well. Almost every Wankel powered aircraft built in the last 10 years uses one of their PSRUs and many use their ECU as well to my knowledge.

People in the market for such products usually find the main players pretty quickly. Letting your site go stale or offline is certainly shooting yourself in the foot and makes people second guess your stability. If you have viable competitors, you will likely lose sales. In the case of RWS, he has no serious competitors and a great rep, simply no need to waste a ton of money marketing.

What we see on other less scrupulous vendor's sites often has little basis in reality but many people fall for hype and shiny new products even if they are not very good. The alternative FF path is littered with broken promises and broken, useless parts to a large degree. If your only concern is the sell stuff to make money short term, with no regard to treating customers truthfully and fairly, you can make money for a while but you will ultimately fail. Dozens of deceitful vendors have found this out.

Marketing mass appeal products is far different from low production, specialty items with regards to return on advertising. I have run such a business for almost 20 years and I can tell you that lots of conventional marketing ideas are simply money down the drain.

One thing that hasn't changed is treating customers truthfully, fairly and giving them good service. Customers will be happy to return again and tell their friends. Surprisingly, many businesses simply don't understand that basic concept. So, out of 7 main Subaru FF component suppliers in the last 10 years who have come along, none remain today. This is why most of the latest build Sube powered aircraft are one offs.
 
Marcotte, RWS

A web presence is important these days for sure if you make or sell any product or service. In the case of RWS, the website and WOM work well....

One thing that hasn't changed is treating customers truthfully, fairly and giving them good service. Customers will be happy to return again and tell their friends. Surprisingly, many businesses simply don't understand that basic concept. So, out of 7 main Subaru FF component suppliers in the last 10 years who have come along, none remain today. This is why most of the latest build Sube powered aircraft are one offs.

Yes. Customer service. Wouldn't it be great if we had a ton more of that.

Subaru drove off. But I guess a Viking ship has arrived. Does the ship have holes in it? Time will tell.

Unfortunately, experimental aviation being what it is, anyone can pitch a tent, sell products and make claims. Ultimately many buyers become the product testers, and with some items, that is definitely not a good thing.

As far as websites, even Vans was guilty of being behind the times on their website design for quite a while. But at least they have some standardization and logical flow of information.

I can't say the same for RWS's website. I have been looking at a lot of it. But I have not seen any recent updates other than on the main page with the green section about parts. The rest of the site seems to be a ghost town of old posts and no updates. Even on his own plane. The "most recent" dates I keep seeing go back to 2003- 2005. Yikes.

So if I were a new person to Oshkosh and got interested and wound up on his web page, it certainly would not fill me with confidence that all was well behind the scenes. It's fine if you are in the know and have done your asking around and research. But anyone new looking at that, it is not going to make a good impression. So he is shooting himself in the foot with that in regards to new viewers who may not have the lowdown on who is who yet. even if after the fact, they hear good things, that initial impression may leave lingering doubts.

Even their customer list with links to their customer's websites is not up to date. More than half of them are dead or useless links.

Such is life in the online world though.

Oshkosh is fun and interesting. But if you are going to get involved, you really have to do your research on vendors or you could wind up throwing a lot of cash out the window, or worse.
 
Subaru drove off. But I guess a Viking ship has arrived. Does the ship have holes in it? Time will tell.

The Viking engine is a better package all together for several reasons, but most importantly it attacks an easier and much larger market. On the other hand several new aero-engines are popping up now, built from scratch for aviation.
 
Yes. Customer service. Wouldn't it be great if we had a ton more of that.

Subaru drove off. But I guess a Viking ship has arrived. Does the ship have holes in it? Time will tell.

Unfortunately, experimental aviation being what it is, anyone can pitch a tent, sell products and make claims. Ultimately many buyers become the product testers, and with some items, that is definitely not a good thing.

As far as websites, even Vans was guilty of being behind the times on their website design for quite a while. But at least they have some standardization and logical flow of information.

I can't say the same for RWS's website. I have been looking at a lot of it. But I have not seen any recent updates other than on the main page with the green section about parts. The rest of the site seems to be a ghost town of old posts and no updates. Even on his own plane. The "most recent" dates I keep seeing go back to 2003- 2005. Yikes.

So if I were a new person to Oshkosh and got interested and wound up on his web page, it certainly would not fill me with confidence that all was well behind the scenes. It's fine if you are in the know and have done your asking around and research. But anyone new looking at that, it is not going to make a good impression. So he is shooting himself in the foot with that in regards to new viewers who may not have the lowdown on who is who yet. even if after the fact, they hear good things, that initial impression may leave lingering doubts.

Even their customer list with links to their customer's websites is not up to date. More than half of them are dead or useless links.

Such is life in the online world though.

Oshkosh is fun and interesting. But if you are going to get involved, you really have to do your research on vendors or you could wind up throwing a lot of cash out the window, or worse.

You make many good and valid points here, especially about customers being beta testers.

Yes, the Viking ship has many holes in it. Again customers were supplied with stuff which was not thoroughly tested before delivery and dissent has been quieted to make things look rosy. Seems some people never learn...

I find Van's site much better than before and it presents the basic information (the important part) well plus their parts ordering system is state of the art, works well with no glitches. As someone who maintains my own company website for 17 years, I find too much hype, useless graphics and cluttered layout often used today does nothing for you except annoy customers. I stick with a traditional, vertical scrolling, informational layout and it works well for us yet, every month I get emails from web developers offering to "improve the look" of our site. Improving the look does nothing to improve our product sales. I have the web/ sales stats and the email complaints to prove it. People often like familiarity. Look at the backlash on Yahoo when there was a format change recently, I know I left at that point.

I think many people who don't run their own businesses don't realize what is involved. When you are swamped with orders, the last thing on your mind and you have time for, is web updates. I know I have a long list of things to do to mine and only managed to make a small dent in the list recently. When business slows down and I have time, I will certainly attend to it. Tracy may be in the same boat. I make money by shipping product out the door, answering sales and tech calls and emails to keep future and existing clients happy, simple as that. If I was twiddling my thumbs, it would be time and I'd have the time to work on the site. I agree though, no updates for 5 years does not look good but more importantly, you have to answer customers promptly and treat them honestly. I am always surprised when customers tell me several other vendors they contacted took a week to reply or never did! Big flashy website but no customer service so they lost the sale right there. I will also tell customers sometimes that our product is not the best choice for what they want to accomplish and even steer them to a competitor. I want a satisfied customer, not just a sale because I am looking down the road and rely on word of mouth to a large degree for future sales.

Bad websites have not sunk any of the Subaru FF vendors, bad products and/or bad business have done most of them in with Maxwell Propulsion being the exception there.

You are right to say that anyone can set up a tent or website and start making claims and sell products and that is often what we see in this field unfortunately. Not much engineering or testing followed by poor customer support. How could anyone go wrong with that recipe?:rolleyes:
 
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The Viking engine is a better package all together for several reasons, but most importantly it attacks an easier and much larger market. On the other hand several new aero-engines are popping up now, built from scratch for aviation.

The Honda engine is great, what is non- factory engineered/ tested and bolted to it is the unknown part.

I do see several new engine designs coming out of Europe now which could be good. Time will tell but I think they will be no cheaper and really no better than existing legacy aero engines, especially from a support/ service standpoint where the legacy suppliers have a huge advantage.
 
Marcotte, Mazda, Vans, Lycoming

I think many people who don't run their own businesses don't realize what is involved. When you are swamped with orders, the last thing on your mind and you have time for, is web updates.

..... I want a satisfied customer, not just a sale because I am looking down the road and rely on word of mouth to a large degree for future sales.

You are right to say that anyone can set up a tent or website and start making claims and sell products and that is often what we see in this field unfortunately. Not much engineering or testing followed by poor customer support. How could anyone go wrong with that recipe?:rolleyes:

Running your own business is more work than working for someone else. That is indeed true. You have to wear all the hats. One big plaque on your desk reads: Human Resources, Sales, Marketing, Customer Service, Accounts Receivable, Accounts Payable, Payroll, Product Development, Web Design and Maintenance, Building Maintenance, Shipping, Receiving, and Marketing.

I doubt many of the companies at Oshkosh actually have engineers on staff save for ones that it really is a necessity. I worked for an "engineering" company for many years. Not once in my entire time there were there any actual licensed engineers on staff. It was a common joke amongst some of the employees. Thankfully, they are not in aviation.

I look at much of what I see at Oshkosh and other places with a very suspicious eye. But that is just how I am. And partially because of places I have worked and things I have seen done. There are others who get excited by the hard sell and perfectly displayed parts, and figure it's experimental anyway, so what the heck, I'll risk my life on it.

I am sure the attitude of some of the companies at Oshkosh and other areas is, why should we hire outside engineering analysis and work hard on getting it right, when we can just sell it to you and let you give us feedback....if you live. First, let's have you sign off on this disclaimer sheet. Cash, check or charge.:rolleyes:

Back to the alternative engine topic. Let's hope that Guy Marcotte, Autoflight, and others, who have successful product designs, look to the future and do what they need to in order to keep the products available for future generations to see, understand, and improve upon. No sense having to reinvent the wheel every generation.

I was following the 4 cylinder Subaru for quite a while. But then the wave of discontent gradually built up on that, and what looked very promising and workable in the beginning, wound up getting a very bad reputation. Not the engine itself, but systems added to it for flight. And here is where the customer service bit and how you approach business becomes very clear.

Coming up with completely new aviation specific engines is without a doubt terribly expensive. And then you are forced to compete on price with Lycoming and Continental who have economies of scale and lots of staff and experience.

The converted auto engines are great if they work consistently and reliably. But the availability of them and spare parts is up to whatever the auto maker does. Corvairs are no longer produced. And nobody is casting engine blocks for them. So you have a limited supply that will eventually get scarce. Same with the Mazda rotary. Finite number of units. Casting of the main body of the rotary is highly specialized. So the shop down the block is not going to be producing them ever. Admittedly, it may take many decades. But eventually it will happen, supply will run out. New auto engines will be considered for conversion as time goes on, and more posts on who can make a psru for it and round and round it goes. No consistency.

That is where being a old dinosaur like Lycoming and Continental have a distinct advantage. It's old, boring, and not exactly high tech. But it works, and continues to have parts availability, plenty of knowledge coast to coast as to how to inspect, maintain, and fix them. They are not the latest and greatest, but they continue to chunk them out, year after year, relatively unchanged since production began long ago, when dinosaurs roamed the planet. Now if we could just get that with new technology at half the cost.
I know...a pipe dream.
 
Perhaps a reason aircraft piston engine development came to a stand still years ago is the turbine engine.

Once jets hit the market their was no incentive to advance an air cooled engine that found a market only on small airplanes - a market always short of money. The only boom general aviation ever had was when the GI bill paid for it. Even at that, there was no incentive to invest in engine development in a market that was so well served with the old piston engines.

Turbine engine development had a huge commercial market, it was more efficient and most important, more reliable and provided for much quicker transportation. None of those features were needed or possible (economically) with light aircraft.

So that leaves us with individuals who are fascinated with the advance of auto engines and the possibility of transferring that advance to a small airplane. My '06 Honda Pilot has 171,005 miles as of today, leaks on oil, uses no oil and is as strong and efficient as the day it was new - wouldn't such service be great in an airplane.

It would be. But no one has come up with a RSRU that is reliable or offers efficiency in terms of weight. The fascination ends there - especially after spending a lot of money experimenting with the idea. Some, like Bud Warren and his daughter, have paid a much higher price. Those who lost only money are lucky.

So as the previous message says, dream on. But endless dreaming does not fill the bill for many of us, I'd rather fly behind a trusty Lycoming than not fly at all, or fly wondering when and where the flight would end.
 
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Running your own business is more work than working for someone else. That is indeed true. You have to wear all the hats. One big plaque on your desk reads: Human Resources, Sales, Marketing, Customer Service, Accounts Receivable, Accounts Payable, Payroll, Product Development, Web Design and Maintenance, Building Maintenance, Shipping, Receiving, and Marketing.

I doubt many of the companies at Oshkosh actually have engineers on staff save for ones that it really is a necessity. I worked for an "engineering" company for many years. Not once in my entire time there were there any actual licensed engineers on staff. It was a common joke amongst some of the employees. Thankfully, they are not in aviation.

I look at much of what I see at Oshkosh and other places with a very suspicious eye. But that is just how I am. And partially because of places I have worked and things I have seen done. There are others who get excited by the hard sell and perfectly displayed parts, and figure it's experimental anyway, so what the heck, I'll risk my life on it.

I am sure the attitude of some of the companies at Oshkosh and other areas is, why should we hire outside engineering analysis and work hard on getting it right, when we can just sell it to you and let you give us feedback....if you live. First, let's have you sign off on this disclaimer sheet. Cash, check or charge.:rolleyes:

Back to the alternative engine topic. Let's hope that Guy Marcotte, Autoflight, and others, who have successful product designs, look to the future and do what they need to in order to keep the products available for future generations to see, understand, and improve upon. No sense having to reinvent the wheel every generation.

I was following the 4 cylinder Subaru for quite a while. But then the wave of discontent gradually built up on that, and what looked very promising and workable in the beginning, wound up getting a very bad reputation. Not the engine itself, but systems added to it for flight. And here is where the customer service bit and how you approach business becomes very clear.

Coming up with completely new aviation specific engines is without a doubt terribly expensive. And then you are forced to compete on price with Lycoming and Continental who have economies of scale and lots of staff and experience.

The converted auto engines are great if they work consistently and reliably. But the availability of them and spare parts is up to whatever the auto maker does. Corvairs are no longer produced. And nobody is casting engine blocks for them. So you have a limited supply that will eventually get scarce. Same with the Mazda rotary. Finite number of units. Casting of the main body of the rotary is highly specialized. So the shop down the block is not going to be producing them ever. Admittedly, it may take many decades. But eventually it will happen, supply will run out. New auto engines will be considered for conversion as time goes on, and more posts on who can make a psru for it and round and round it goes. No consistency.

That is where being a old dinosaur like Lycoming and Continental have a distinct advantage. It's old, boring, and not exactly high tech. But it works, and continues to have parts availability, plenty of knowledge coast to coast as to how to inspect, maintain, and fix them. They are not the latest and greatest, but they continue to chunk them out, year after year, relatively unchanged since production began long ago, when dinosaurs roamed the planet. Now if we could just get that with new technology at half the cost.
I know...a pipe dream.

Very good post. This is pretty much how I see things as well on this topic.
 
You don't have a dual mass flywheel, and it's not a damper.

Well I'm glad to know you're an expert on my airplane. I guess the 2 pieces of my flywheel coupled with a spring are just pretending to be a dual mass flywheel and all car manufacturers that use them only use them for the extra weight not the damping.

-Andy
 
There have been catastrophic failures of the Gen 3 boxes. Do you remember the one that ended up on federal land last year? "Very reliable" is not the words I'd use to describe these boxes. Broken welds, broken input shafts, disintegrating flywheels, bearings shedding metal, leaking seals, serious F1 kickback for a good percentage of users etc.

I am glad your box is working well with over 500 hours on it, many others have not been so fortunate.

I do agree that Jan should have stuck with the fours and that with the right combination of parts, they can work well and be more competitive in the weight department.

I am glad to see your post here so people can see that there are successes. You are happy and stuck with it unlike many others.:)

I do remember that failure where the aircraft landed on federal land. It was a failure of the spined shaft and caused Jan to recommend grounding all non-dual mass flywheel installations. All the failures you mention occured with non dual mass installations, or are failures of other parts, not the gearbox.

I'm glad to see all the work you are doing for the alternative engine community, I just hate to see people pass up a reliable option.

-Andy
 
Well I'm glad to know you're an expert on my airplane. I guess the 2 pieces of my flywheel coupled with a spring are just pretending to be a dual mass flywheel and all car manufacturers that use them only use them for the extra weight not the damping.

Always glad to help.

2008 was a bit before you joined us. Read these:

http://www.vansairforce.com/community/showpost.php?p=196375&postcount=30

http://www.vansairforce.com/community/showpost.php?p=196489&postcount=33

As for being a damper, please study the following classical illustration. You'll find one like it in the first chapter of any serious text on vibration.

28ckrph.jpg


In this particular example.....

k = spring rate
m = mass
B = damping coefficient
F = force

You have a k and you have an m....but you have no B.
 
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I do see several new engine designs coming out of Europe now which could be good. Time will tell but I think they will be no cheaper and really no better than existing legacy aero engines, especially from a support/ service standpoint where the legacy suppliers have a huge advantage.

What exactly is a "legacy" engine? The Rotax 912 has been around for some time now, is that a legacy engine (it's 25 years old, more than 40 thousand units sold) ? An engine is an engine in my opinion.

The main thing is the market for aero-engines and how that is changing. Everything else is minor compared with the market governed by rules and regulations.

The 912 was created for the UL market in Europe that really took off in the late 90's in it's modern form with high performance light aircrafts (carbon composites, advanced aerodynamics etc). Later came the Light Sport in NA, and the 912 fits right in there as well since most LS aircrafts are modified European ULs.

Since the European ULs performs better than legacy private aeroplanes (Cessna types) in almost every category except MTOW, and is considerably cheaper and simpler to purchase and operate, UL is blooming and legacy is withering away. The same thing is happening in NA with LSA blooming. The other thing that happened, was the 912 (along with a few other purpose built aero engines) also wiped away the competition consisting of VW conversions, motorcycle engine conversions and so on.

Right now the market for 150+ ish HP engines is fading away while the 80-120 HP range is blooming, but it is blooming mainly for purpose built aero engines. The Viking engine is simply surfing the wave, but will it last when people start to sell their used aircrafts with an auto conversion? That depends entirely on the quality of the engine and customer relation.

But more things are happening in Europe. The new categories ELA1/ELA2 and CS-LSA are already here. The CS-LSA is a European version of the LSA (with some modifications), while ELA1/ELA2 is an "LSA" class with MTOW 1000/1200 kg (2200/2600 lb). The UL class will still be there and also the old private aeroplane category of MTOW 5700 kg. The CS-LSA and ELA1/ELA2 are certified classes (unlike UL), but with much simpler certification process and maintenance system than the legacy private aeroplane. ULPower is heading straight into that direction with their 6 cylinder engines.

So, there will eventually be a market also for the 150-200 HP category of engines with much relaxed certification processes. Then we will see if people want old manually operated dinosaurs or modern light weight FADEC engines.

For the first time since WWII at least, do we now have a real market and a real ecosystem for GA in Europe. Manufacturers of aviation products can start with UL (no certification of any kind), then move up the ladders CS-LSA, ELA1/2 (easy and cheap certification) all the way to commercial airline type products. In theory a manufacturer can produce the same basic airframe with the same basic engine and avionics in UL, CS-LSA, ELA1/2 and even a commercial GA with only minor changes (more or less), and this is exactly what they do. Earlier, before UL became a reality, they had to start directly with commercial GA type certification (for airframe and engines). An impossible task for anybody except those with tons of money somewhere, and even with tons of money, why head into a dwindling market? This is the main reason why Lycoming have survived all these years (with no development since the 50s), but this is all changing now.

Experimental aviation will only benefit from this, with more products to chose from, engines and avionics in particular.
 
I do remember that failure where the aircraft landed on federal land. It was a failure of the spined shaft and caused Jan to recommend grounding all non-dual mass flywheel installations. All the failures you mention occured with non dual mass installations, or are failures of other parts, not the gearbox.

I'm glad to see all the work you are doing for the alternative engine community, I just hate to see people pass up a reliable option.

-Andy

Sorry Andy, you are not correct with your statement here. Many of the failures I listed have also happened to engines fitted with the "dual mass" flywheel. The input shaft is part of the gearbox system also. Jan is no engineer and never did any TV testing on these gearboxes so why would you think the change in flywheel will solve all the problems? I hope you are right but there is no science to back this up.
 
All the failures you mention occured with non dual mass installations, or are failures of other parts, not the gearbox.


Hi Andy,
We have two verified failures of Gen 3 v4 gearbox internal parts, both were cracked welds where a gear was welded to a shaft. You are correct that these happened on "non dual mass" setups, but it is not completely correct to say there have been no failures with the gearbox.

We have also had several reported issues with the spline shaft (the shaft that connects between the engine and the gearbox), with the believed but not confirmed cause being misalignment of the gearbox to the engine when installed. Other minor issues have also been reported such as leaking seals.

I am a supporter of these engine packages as much as you are, and I hope to fly behind my 2009 E6 package one day. For safety reasons, I also support full disclosure so if there are any issues, however slight, we owe it to ourselves to discuss openly and work together to find solutions.

Just last week a Cessna 172 landed at my airport with oil streaming down the side and bottom of the cowling, with less than 2 qts left in the engine. A retaining clip had separated inside the valve cover, jammed sideways between a valve and the cover, thus piercing the valve cover allowing the oil to be pumped out. Just pointing out that even the little things are important.
 
Successes

One of the European Subaru users posted on Subenews today that he flew in his friend's IO-360/ Hartzell 7 recently. At the same fuel flows, the Lyc was 10-15 knots faster than his EZ30T with MT prop. His friend had all fairings on though and his plane has had the wheel fairings removed for winter operation so call it 5-7 knots faster or so.

He was appalled by the din though when he removed the headphones and the high vibration levels, especially through the floor pan compared to the Sube. He is so happy with the Sube, he is planning on building a new 7 with an EZ36 soon.

He has 247 hours on his EZ30T with no real problems.

Of course, there are many other success stories I could relate along with the tales of woe. I like to give a realistic balance of the experiences. Some people are pretty happy (even very happy) while others have been disgusted with the whole thing and replaced the FF with Lycoming. When these things work as intended, they are wonderfully smooth and trouble free.:)
 
Ross,

I can not resist responding to your report on Subby smoothness, noise and floor vibration as reported from Europe.

Yes, the operation is SMOOTH, no debate there - except the floor.

It is my experience (after some 400 hours behind 2 engines) even with mufflers, the Subby is very noisy (about the same as Lycoming with 4 straight pipes) And with the Egg muffler hangers from the bottom floor, the floor was ALIVE to the point I wondered about eventual skin failure.

The pipes induce vibration, a lot of it. Maybe that's why the rest of it seems so smooth. The canopy rail is dead smooth but not the floor under your shoe. :)
 
Ross,

I can not resist responding to your report on Subby smoothness, noise and floor vibration as reported from Europe.

Yes, the operation is SMOOTH, no debate there - except the floor.

It is my experience (after some 400 hours behind 2 engines) even with mufflers, the Subby is very noisy (about the same as Lycoming with 4 straight pipes) And with the Egg muffler hangers from the bottom floor, the floor was ALIVE to the point I wondered about eventual skin failure.

The pipes induce vibration, a lot of it. Maybe that's why the rest of it seems so smooth. The canopy rail is dead smooth but not the floor under your shoe. :)

This is the turbo engine. Way quieter and totally different noise signature from the atmo Subes. My turbo 4 and the STi up here too, very quiet inside and out. That's why I like turbos, quiet, powerful, smooth.

I agree, the atmo EZs are painful above 4500 rpm with a very piercing and annoying note inside the aircraft.
 
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Waiex on Barnstormers

Speaking of alternative and customer service.

There is a Waiex for sale on Barnstormers with a Viking Engine by some guy name Jan. Curiously no photos of the engine posted.
 
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